Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 22·2.8
Proprietary ventilation assemblies
When using proprietary assembly ventilation systems, the equivalent free area should be taken from the manufacturer's specified value.
Where ventilation is to be provided via a single proprietary assembly the equivalent free area of the air vent should be taken to be the manufacturer's value. The manufacturer may call this a free area or equivalent free area.
See Diagram 2.1(a).
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